Cast refractory block and method of producing the same



May 2l, 1940. G. s. FuLcHER 2,201,123

CAST REFRACTORY BLOCK AND METHOD 0F PRODUCING THE SAME Filed Sept. 28. 1937 Patented May 21, 1940 PATENT oFFlcE CAST 'REFRACTORY BLOCK AND METHOD F PRODUCING THE SAME Gordon S. Fulcher, Louisville, Ky., assignor to Corhart Refractories Company, Louisville, Ky.

Application September 28, 1937, Serial No. 166,155

4 Claims.

One of the serious problems attending the casting of refractory materials from the melts thereof is the formation of pipes in the casting during the cooling ofthe material from its cast- 5 ing temperature (approximately 1800 C.) to its setting temperature. This pipe tendsto form at the top of the cast block where the font was located in the casting, destroying the smooth finish of the casting at that point and creating ,10 a cavity which may form the center of attack if molten glass enters it. The present invention has for its object to convert the space formed by the contraction from a pipe such as has hitherto been formed, into a cavity entirely enclosed Within the surface of the block, and this I accomplish by turning the block around a horizontal axis during the period of its setting. My invention, therefore,`consists of such process as well as the product resulting therefrom.

Referring to the accompanying drawing in which corresponding parts are ,designated by corresponding marks of reference,

Figure 1 represents in section a mold by which my invention may be carried out.` p 26 Figure 2 shows such a mold after it has been filled with the molten material and closed.

Figures 3 and 4 represent the mold in a rocking frame constructed in accordance with this invention.

80 Figure 5 is a diagrammatic view of the rocking frame shown in Figures 3 and 4 with means for rocking the same.

Figure 6 is a diagrammatic section through a block embodying my invention and having two 3B enclosed cavities. l

The mold II of a well known construction is enclosed in a metal flask I2, the mold having a top plate I3 with a font .I4 thereon. After the mold is filled with the molten material the top d0 plate I3 and the font I4 are removed and replaced by a refractory slab I5, and a cover I6 is clamped thereon with a layer of insulation |65 interposed between them.

The flask is now clamped in a rocking frame 45 consisting of two wheels I'I, each having a frameworkl I8 |built within itslperiphery and provided with screws I9 to clamp the opposite ends of the ilask, which during the time it is being fixed in position may rest on a stand 20.

Upon removing Ithe stand from beneath the flask the wheels may be rolled along a suitable track. As a convenient device for this purpose the wheels may run on an inclined track 2i being pulled up the track by ropes 22 and a windlass 55 23, and after being pulled up for half a turn the wheels may be released to roll back to the lower position. Obviously, other means may be re` sorted to for rocking or rotating the casting on a horizontal axis. The motion around this axis so may be and preferably is slow (say, one complete cycle in ten minutes) to permit the molten material to be spread over all sides of the mold by the movement of the box and to solidify thereon and without washing the solidified material out of place. 'Under such treatment the molten mate- 6 rial will solidify in layers on all six sides of the flask (including what was the top thereof), thus locating the cavity, which is necessarily formed by the contraction of the molten material, more or less in the center of the casting.

For certain purposes it is desirable that the central section of the casting be solid. I can accomplish this, according to this invention, by rocking the horizontal axis of the block during solidifcation through an angle of 45 to one side to a'45 angle on the other once every five or ten minutes during cooling. In this operation the central section, which is lled with the liquid at all times, will become practically solid. In Figure 6 the dotted lines indicate the thickness of the wall at successive stages of cooling. It is believed that for certain purposes the location of the cavities in the ends of the block is preferable to any other situation.

Instead of rocking the block back and forth during all or a substantial part of the time it is solidifying, it may be simply turned on a horizontal axis after the casting and permitted to stay stationary in this turned position with one end higher than the other during the solidication, whereby the cavity resulting from the contraction oi the 4material will be found in the upper end.

Having claim is:

l. 'Ihe hereinbefore described method of casting and solidifying a refractory block from molten material which comprises pouring the molten material into a mold having the intended shape and size of the cast article and thereafter during solidiflcation, turning the casting and mold around a horizontal axis.

2. The hereinbefore described method of casting and solidifying a refractory block from molten material which comprises pouring the molten material into a mold having the intended shape and size of the cast article and thereafter during its soldilcation slowly rocking the casting and mold around a horizontal axis.

3. A cast block of refractory material, having the cavities resulting from the contraction of such material during cooling located at opposite ends of the block.

4. A cast block of refractory material, and having the cavity resulting from the contraction of such material during solidiication substantially symmetrical in respect to an axis of the block which was horizontal during the casting and entirely enclosed.

thus described my invention, what I GORDON S. FULCHER. 

